Optical Fiber Gratings Immunoassays

Area of Science:

• Biomedical Engineering
• Optical Sensing
• Nanotechnology

Background:

• Optical fibers are increasingly utilized for biosensing applications, particularly in point-of-care diagnostics.
• Tilted Fiber Bragg Gratings (TFBGs) are highly sensitive refractometers, making them suitable for detecting low analyte concentrations.

Purpose of the Study:

• To explore and compare different biofunctionalized TFBG configurations for label-free immunoassay development.
• To assess the performance of TFBGs in detecting cancer biomarkers for biomedical applications.

Main Methods:

• Biofunctionalization of bare, gold-sputtered, and gold-electroless-plated (ELP) TFBG configurations with antibodies.
• Utilizing TFBGs as refractometers for label-free detection of cancer biomarkers.
• Evaluating the limit of detection and performance in laboratory and ex vivo settings.

Main Results:

• Different TFBG configurations exhibited unique characteristics, influencing their suitability for specific applications.
• The most sensitive configuration achieved a limit of detection of 10^-12 g/mL under laboratory conditions.
• Successful ex vivo application of the TFBG biosensor in freshly resected lung tissues was demonstrated.

Conclusions:

• TFBGs provide a versatile platform for label-free immunoassay development in biosensing.
• The choice of TFBG configuration is critical and application-dependent for optimal performance.
• The study highlights the potential of TFBG biosensors for sensitive cancer biomarker detection in clinical settings.